The present invention relates to a new antibiotic, which we have called "chloropolysporin", to a process for its preparation by the cultivation of a newly discovered microorganism and to its use, both therapeutic, in the treatment and prophylaxis of infections caused by bacteria, and as a growth-promoting agent for animals.
As resistance to conventional antibiotics becomes increasingly established in common strains of pathogenic bacteria, the need for a wider variety of antibiotics for use in the fight against such bacteria becomes ever more crucial. Moreover, various antibiotics, for example chloramphenicol, aureomycin, vancomycin and avoparcin, have been administered or have been proposed for administration to poultry and other farm animals, including the ruminants and pigs, for the prophylaxis of disease or to promote growth of milk production. However, an inherent disadvantage of the use of antibiotics in this way is that there is some risk that traces of the antibiotics or of metabolic products thereof may be found in animal products intended for human consumption (such as eggs, milk or meat); the alleged dangers of such residues are increasingly criticized by some sections of the community. There is, accordingly, a considerable desire amongst farmers for an antibiotic substance which will have the desired growth-promoting effect but which will leave no or no significant residues in animal products.
We have now discovered a new microorganism, which we have assigned to the genus Micropolyspora, and which produces a new antibiotic substance that is highly effective against gram-positive bacteria and that shows considerable promise for use as a growth-promoting agent in animals.